The present study investigated how trait mindfulness is related to anxiety and aggression by considering the mediating role of resilience with the longitudinal data among Chinese college students with left-behind experience. A total of 391 Chinese college students with left-behind experiences completed the Mindful Attention Awareness Scale, the Connor-Davidson Resilience Scale, the Chinese college students' version of the Buss-Perry Aggression Questionnaire, and the Depression Anxiety Stress Scales at two-time points. Structural equation modeling was used to analyze the data, and the results indicated that resilience (T1) mediated the relationship between trait mindfulness (T1) and anxiety (T2) (indirect effect = -0.053, 95% confidence interval [CI] = [-0.119, -0.005]) as well as aggression (T2) (indirect effect = -0.070, 95% CI = [-0.127, -0.029]). Therefore, trait mindfulness had direct and indirect negative associations with anxiety and aggression, and resilience mediated the relationship between trait mindfulness and both anxiety and aggression. The findings of the study provide valuable insights into the potential benefits of trait mindfulness and resilience in improving mental health outcomes and suggest clinical potential in the improvement of mental health among college students with left-behind experiences.